| 摘要 |
A channel data transmission system is described, which data are structured channel-sequentially in frames and/or multiple frames. Such transmission systems are used, for example, for video conferencing during which data are exchanged over ISDN base channels. Since the bit rate, at which video codecs exchange their data, exceeds the bit rate, at which data can be transmitted over a base channel, no less than two base channels are to be provided for the intended data exchange. The signals of these base channels may be variably delayed on their way to the receiver. Cancelling this delay difference for a maximum of thirty base channels is the essential object of the multiplexer described. For achieving this object the received data (1a) of the base channels are channel-sequentially arranged and written in an addressable main memory (3). Detection means (11, 13, 13A, 14, 15, 16) are to detect frames and multiple frames among the stored data of one of each of the channels. If a frame or a multiple frame is detected in the data of a channel, the addressing means (6) are set with the aid of control means ( 4, 5, 16) so that, for example, the beginning of a multiple frame obtains a predetermined write address. The data of all the channels are multiplexed in that they are read out from the main memory (3).
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